Sept. 4, 2013— -- On his 17th birthday two years ago, Peter Srsich, a high school lacrosse player and devout Roman Catholic, saw his faith hit rock bottom while undergoing seven rounds of grueling chemotherapy and 21 days of radiation for non-Hodgkins lymphoma.
"I was on the pain killer Dilaudid and was diagnosed with depression at the time," said Srsich, who was being treated at Children's Hospital in Aurora, Colo. "Things had kind of started to pile up, and I started questioning, why would this happen?"
But his faith returned when his friend brought the Eucharist to his hospital bed and the teen said he felt the uplifting presence of God.
His ordeal began just before the end of his junior year in high school, when he developed a cough. Then that summer, still suffering with the cough, he returned from a canoe trip to Minnesota and found himself overwhelmed with fatigue. It was "a different tired than I had ever felt before," he told ABCNews.com.
What at first looked like pneumonia, turned out to be a softball-sized mass on his left lung that was compressing his heart.
"It was so large, they couldn't put me under anesthesia because there was a risk I wouldn't wake up, so they couldn't even get a biopsy of it," Srsich said.
But today at 19, Srsich is in remission, again active in athletics at Regis University, a Jesuit college in Denver, and on the path to the priesthood.
He thanks his doctors for his physical recovery, but he credits his spiritual rebound to one of the most unusual and logistically complicated requests ever asked of the Make-A-Wish Foundation -- to meet the Pope.
"The one good thing is in a young person who is healthy and strong, it's very curable. But the treatment is horrible because they use such intense drugs." -- Laura Srsich
Last May, Srsich, his mother Laura and father Tom, and his then 15-year-old brother Johnny flew to Rome for a week where Pope Benedict blessed the teen, before resigning the following February.
This week, one Catholic blog jumped on Srsich's recovery story, calling his audience with the outgoing pope the reason for his "cancer cure." But Srsich laughed, saying he has faith in both God and science.
"I credit all the years of medical research and the training of all the doctors going to school -- all that definitely cured me," he said. "But God was behind it, helping me go through the treatment. Medical science is phenomenal. It would have been a death sentence 30 years ago, but in less than a year, I am back on my feet."
Pope Benedict resigns amid questions.
The teen's journey began with his diagnosis in July 2011. At first, doctors had no idea how to treat Srsich without triggering a heart attack. Then came the frightening diagnosis: stage four cancer.
"The one good thing is in a young person who is healthy and strong, it's very curable," said his mother, Laura Srsich, 50. "But the treatment is horrible because they use such intense drugs. He had seven rounds of chemotherapy in the course of six months."
Srsich missed nearly his entire senior year of high school but was able to attend the prom and was named homecoming king, even though he was completely bald.
One of his classmates, knowing Srsich was religious, created 1,200 lime green rubber wristbands: "Praying for Peter." The bands cited the teen's favorite Biblical passage, Romans 8:28 -- "And we know that in all things God works for the good of those who love him, who have been called according to his purpose."
The bands went round the world, according to his mother. "He had a huge amount of people praying for him."
Meanwhile, three months in to chemotherapy and radiation, Srsich got a visit in the hospital from the Colorado Make-A-Wish Foundation, which helps about 250 children a year realize a dream come true.
"At first I was a little concerned -- I thought [of it] as for terminally sick children who had no chance and were getting one last wish," he said. "I thought there was something the doctors were not telling me."
But after chatting, he told them his top wish was to go to Rome to see the Pope, not just to go to Disneyworld or meet Justin Bieber.
"I would have been perfectly fine if I just got a tour of the Vatican," he said.
Srsich met the criteria: "a child with a life-threatening medical condition, progressive and malignant at the time of the referral [by a physician]," according to the national Make a Wish Foundation.
"There have been wishes more complicated, wishes that cost more money," said Jennifer Mace-Walton, director of wish giving. "His was one of the most unique."
The $14,000 trip, which included airfare, hotel, food and spending, was arranged with the help of the Italian chapter of the organization.
"After meeting Peter, there was no doubt in my mind it was his true wish and it was going to play an important role in what he wants to do career-wise," said his gift coordinator LuAnn Griffin.
The immediate family was thrilled to be able to hear the pope speak in five languages before a large audience. Afterward, they were called to stand before him in a line of dignitaries, including five-star generals from the Italian army.
"At that point, I realized I would get to have a conversation with him," Srsich said. "Everyone was bringing gifts and I started freaking out.
"I am standing like the little drummer boy with nothing to offer," he said. "There were golden crowns and a 4-foot tall magnificent painting of Mary and I am sitting there with a 70-cent rubber wristband."
His father handed the teen his wristband, the one that said, "Pray for Peter."
At 6-foot-6, Srsich towered over the short Pope and after a two-minute introduction, told him about his cancer, asking for a blessing.
"He looked at me and said, 'Oh, you speak English?' and put his hand on my chest right where the tumor had been, even though I had not mentioned it to him," he said. "The blessing is usually on the head."
Srsich said he was "in awe of how humble he was."
Today, Srisich feels "wonderful" and is back playing college lacrosse and is soon testing for his master in Taekwondo. And, despite the medical set-back, he is still on track to be an ordained priest in about eight years time.
"Every time people see cancer and the pope, they assume it's a miraculous healing," he said. "Chemo helped me fight the cancer. Make-A-Wish helped me fight the chemo. Knowing the pope was in my future helped me get through that, and in a small, non-miraculous way, helped cure my cancer."